Clutch and clutch control mechanism



Aug. 16, 1949. E. E. wEMP 2,479,532

CLUTCH AND CLUTCH CONTROL MECHANISM l Filed OC. l5, 1945 I 6 Sheets-Sheet l nulli." o

N INVENTOR Tfr/e525 E #Ka/77,0

TTORNEY Aug. 16, 1949. E. E. wEMP CLUTCH AND CLUTCH CONTROL MECHANISM 6 Sheets-Sheet 2 Filed Oct. l5, 1943 .y TORNEY6 1 INVENTOR ZT/76.95 Z.' 4f/27p Filed Oct. l5, 1945 Aug. 16, 1949. E, E, WEMP l2,479,532?

AND v CLUTCH CONTROL MECHANISM 'CLUTCH 6 Sheets-Sheet 3 DIS' ENGAGEMENT ENGA GEMEN T `SIDE e C t? 87 l ee INVENTOR ,Eff/m65 #Komp IF: g BY I l i n A TCRNMA Aug. 16, 1949. E. E, wEMP 2,479,532

CLUTCH AND CLUTCH CONTROL MECHANISM Filed Oct. l5, 1943 6 Sheets-Sheet 4 @o OO 47 |NvENToR Taef Z5.' l/Vmp ATTORNEYS Aug. 16, 1949. v E, E, wEMP 2,479,532

CLUTCH AND CLUTCH CONTROL `'MECHANISM Filled Oct.a l5, 1945 6 Sheets-Sheet 5 13o a? 86 Q Ais V nu www l uw /Illt' C I /3/ INVENToR Ef/'H656 E 'fl/@mp E. E. wEMP CLUTCH AND CLUTCH CON'ROL MECHANISM Aug. 16, 1949.I

' 6 Sheets-Sheet'l 6 Filed Oct. l5, 1945 INVENTOR Z'rwes EWI/emp Patented Aug. 16, 1949 UNITED STATES PATENT OFFICE CLUTCH AND CLUTCH CONTROL MECHANISM 13 Claims.

This invention has to do with the transmission of power from a power source to driven means, where the torque line is to be interrupted at times for one purpose or another and then reestablished. The invention is concerned particularly with an arrangement for the transmission of power from an engine in an automotive vehicle where the engine is to be disconnected from the traction wheels of the vehicle for the changing of gears to eiect different driving ratios and to permit the engine to run while the vehicle is at rest.

The invention relates to what may be termed a clutch and clutch control arrangement wherein the clutch is engageable and disengageable for gear shifting purposes or the like. In accordance with the invention a centrifugal clutch is provided which is designed to be disengaged at engine idling speeds but which becomes engaged upon acceleration of the engine above idling speeds. Thus the clutch is of an automatic nature. The engine referred to in the specic disclosure herein is 'an internal combustion engine which may be of the usual and well known type. In conjunction with the centrifugal clutch, are means for eiecting clutch control and for supplementing the clutch packing pressure. In this connection the centrifugal clutch is relatively lightly centrifugally weighted so that the clutch, when acting under centrifugal force alone, is not capable of transmitting full engine torque until the engine has reached a fairly high R. P. M. The means for supplementing the clutch packing pressure is preferably a hydraulic arrangement, operable from a driven member, i. e. a member which operates only upon movement of the vehicle.

One f the objects of the invention is to provide an arrangement wherein the centrifugal clutch is. disengaged at normal idling speed so that the engine may be running while the vehicle is at rest but which engages centrifugally upon acceleration of the engine above idling speed to initiate vehicle movement. The hydraulic system begins to function at a relatively low speed of movement of the vehicle. However, when the vehicle is decelerated the hydraulic system holds the clutch engaged at engine R. P. M. lower than the R. P. M. at which the clutch would dis-engage centrifugally. Therefore, the engine and the traction wheels remain coupled together upon the deceleration of the vehicle below the speed at `which the centrifugal. clutch would otherwise become disengaged.

A further object of the invention is to provide a nicety of clutch engagement which is afforded by the lightiy weighted centrifugal clutch and wherein the packing pressure of the clutch is supplemented by the hydraulic system to prothan the speed where the centrifugal system is capable of providing clutch packing pressure sufficient for transmitting full engine torque.

Another object is to provide an arrangement where the end thrust caused by the hydraulic system is relieved at vehicle speeds at which vehicles quite usually are normally operated.

A further object of the invention is to provide a centrifugal clutch and a hydraulic control and pressure supplementing means wherein the hydraulic pressure is variable in a manner similar to the variation of centrifugal force with variation in R. P. M. It is of course well known that centrifugal force increases with the square of the speed; the hydraulic system advantageously embodies a pump arrangement functioning from centrifugal head and velocity head of the liquid, both of which increase with the square of the speed. Thus the pump constitutes both a pump and pressure regulator. In other words, there is a pumping action upon vehicle movement and the pressure thereof varies with the square of the speed.` This liquid pressure is employed to supplement the clutch packing pressure and to also release the clutch against centrifugal force at any speed of operation. Obviously, it takes more force to release the clutch against centrifugal action at high R. P. M. than it does at low R. P. M. but since the liquid pressure varies with the square of the speed as does the centrifugal force of the clutch, the pressure is adequate to disengage the clutch at any operating R. P. M.

A still further object of the invention is to standardize the procedure of clutch release and clutch engagement, while at the same time a1- lowing the individual operator a wide latitude for the exercise of his own prerogatives in driving the vehicle. To this end, clutch disengagement and clutch engagement is eifected automatically through the hydraulic system when, for example, there is to be a shift of gears made While the clutch is disengaged. The manner of engagement of a clutch, however, cannot be disassociated from the relative engine and vehicle speeds. Some operators operate the engine at a high R. P. M. just prior to clutch engagement, with the result there is considerable clutch slippage before the engagement is complete. Other operators attempt, more or less, to synchronize the engine R. P. M. with vehicle speed for a minimum of clutch slippage, In accordance with this last mentioned object of this invention, the control of the operation of the engine is automatically governed during the period of clutch disengagement and engagement. In other words, the automatic operation of the clutch is coordinated with an automatic control of the engine. To this end, the operator of a vehicle who desires to effect a change of gears performs a gear shiftvicle adequate torque Capacity at speeds lower Y 50 ing action which results in automatic clutch dis- 3 engagement, and before the clutch is disengaged the contro-l of the throttle of the engine is taken over by the automatic means, 1n other words, the oper-atiomo.` the engine is taken out oiv the controlof the driver and is governed'by the clutch operating means. After the clutch has openld and the gear shift made, the driver, having completed the gear shift, discontinuos-thee manual control and the clutch then begins to re-engagell When the clutch is sufficiently engaged.` the con.- trol of the throttle is released by the automaticmeans and restored to thexirivor.` "Thus-.it will;f be observed that the engine is not under the control of the driver during that period beginning'in the disengaging action, continuing while the fclutclris disengaged; and until Athe-.clutcl'r-is again fatrleast. partially engaged.v Yet'therefis nodictation: asfto when anindividua-l driver.` maymakea shiftr of:I gears; this is .left lto the driver lto=exercise his Yown ideas and. preferences ofi` what. may, or f -imayrnot-be Anecessary. to meet: the' exigenciesfof the situation. This phase of the invention will loe-better understood. asy also will. other objects foffthe invention When-.the detailed description is considerednn. conjunction. with .thevv accompanying-drawings which show one form ofi apparatus for-carryingout theinvention in addition: toa modiledform.v of' control.

Eiggl is a crosssectlonalview showingeacentrif- ,ug-al' clutch and a liquidf pump arrangement mountedin a bell housingassoci'ated'withanfinternal t combustion eng-ine;

Fig. 21s sectional'` view'ftaken substantially on line-'2 2' of Fig. 1.

lig;"3. isV a rearelevationa-l view.- oftI the centrifn- 'gal clutch.

F'ig; LLis .a sectional view taleenfsubst/aritiallyfon line d-dofFig; 3-1illustrating: ai clutch` detail:

'Figa 5` isan elevational View taken substantially fonfli'nef-E--S-of'ligzll showing the-pumpistructure v V fand' illustratingA some of thepartsin dotted?l lines. .Figw is anelevationarvieW-offthe.oppositeside of the-pumpstructure and taken=substantiailyon -line G-Bi of 1 Fig.. V1. zFig. 17` is a sectional yvievv'taken substantially fon linef 7-.1 of.' Fig. 62

Fig. 8 is a vievvofthel clutchoperatingfcylinder 'showrrin- Eig; 12; lookingffrom the-righthandfside 'offllig. lzzandl'showingrsorneo'f the passageways dottedylines.

Fig. Q'is` aside el'evationalrlviewof-f' theeclutchor 'bni housing il'hlst'-llgvarious control mechanism: for the' clutch and for vthe throttle of 'the engine.

ftnereon. and ilmsn-anng the piping. of the nydraulic system.

fing. `12 is a Vseccional*View11a-kenamarga the 'clutchoperating cylinder,

Fig. 1'3is a'sectionaliviewitaleen throughfthe cylinder Ain the throttle-control' system.

vliig. 1-4 is asectli'onal view taken through the solenoid valve lof the hydraulic system showing 'the' valvein VAclutch engagement'Y 'psitiom 'Fig'. 15 Vis a sectional-viewfsimilar to Fig; 14

' 'showing the valvein clutch-released position.

' "'Fig. 16= isa-sectional' View 'through theL ria-anual'` "control handle and taker-r-atrightcangleswtofthe illustration thereof `in Fig. 14.

Fig.` 17' is a sectionalfview taken substantially tertting parts in the control system illustrated in section in Fig. 10.

Fig. 19 is arview, largely inside elevation showing -za modified form ofengine-throttle; control.

Fig. 20` is a view similar to Fig. 11 showing in elevation the control cylinder and piping of the modied form.

Inlfig; f1' arr-.engine block is illustrated at l, the .crank shaft at 2 and the ywheel at 3 which is positioned within the clutch housing fr. A driven Yshaft Tis'piloted at one end in the flywheel, as

shown; and extends through the housing l and into a gear box S containing shiftable gears for varying --the speed ratio between the driven shaft 5 and propeller shaft 1.. The gears may be shifted thmughl tio-ei` means: .of a suitable Vshiftahle element. suchf.;as;a rod orr the likefS.

'Ihecentrifugal clutch includes a; covenV plate Hl .boltedzto thejiiywheei Yandainrosa/111e'plate M. The-fpressure plate-and theywheel are adapted .tnzeneagebetweenthemthefacings l 2 cfar driven The-facings areznormally'held yieldable spaced apartfby fsuitablef yieldingmeans M. Argnnrnberofiforgms ofv` such yielding meansmare; well known to `those versedfin the :art:

Mounted on the cover plate are bracketslflg (-Eig. 49 which aref attached. to the, inside; o f: the cover 5 plate. ;each ov which has: a. pair of projections or `ears 'In extending out. throughan opening; in Ythe `c oveuplateas shownin Eig. .'Iherearethreeof suehzbraclse-ts-and-.the-pressure-.plate H has provleftilog:tongues; l which lie between the earsgl. 'Iihusethe pressure y plate is 3 drivingly` associated witlrthe cover platfand'it can be shifted-axially. pnessureplate. isnormally retracted into a clutchndisengagedposition? by springs 28. Asf-Wi-ll `laterappear.the; action of the springs '20 maybe supplemented,bymeans-locatedioutside the housing.; ,A ccmbinedfleverranld; centrifugal weight .is-mounted between each.` pair of; phoiectionsy t8 on aininfZZ advantageously*through-.themeans 0:1 `@edlerroller-bearings as shownandeaoh has "arweightedsmass le and an. inwardly extending lever arIrrgZll providedonitsend. with an involute Mteutl'rJ 2.5. Each Weighted. lever enga-ges.r the adjacentrcprojectingf tongue of: thel press-ure plate aszindicatedfat 2n. It willv be apparent thatthe weighted.:massespxiovide an unbalanced condi- "tionfso that upon.: rotation the levers are swung on their-axes so thatthe lever arms 215i shift to the right as Fig. 1 is viewed and the pressure-plate iszpushcd v'tno' .the left; and into engagement-with fthefdriyen disc.

Afclntchi control-shaft i28 has. a yoke29 thereon,

V.therend sof` the; arms of which are engaged with azcntrclr-:sleevefn through the Vmeans ofpin and islotfconnections'l sothat the yoke 'may shift the control' sleeve in both directions. An anti- '.fr-iction bearingfSZ connects. the control sleeve fwithuacontrolf sleeve part or element 33 having ment of the control sleeve and vice versa.Y As

-s=hown..-in=1ig. I3, there are three of the combined weight and lever elements.

The pump shown herein is mounted: in the housing r4" which is: divided by a partition 35 to provide asumpohamber 36. This pump comprises essentially two elements, namely, a shell or casing-and-Pitot tube mounted for relative rotation. AThe `shell has one Wall mounted on a hub 33 'Whionfis---fkeyed' totherdriven shaftl While the other wall, which is axially spaced from the first wall, has a central opening 39. A hub element 49 journaled on the driven shaft has a radial extending arm 4|, on the end of which is a head 42. There is an opening 43 in the head which opens substantially tangentially and a passage 44 extending through the arm and hub and to an outlet 45. An outlet pipe 46 connects at 45 and extends out through the wall of the housing 4 to an outlet iitting 41 (Fig. 9).

In the operation of the pump, the shell rotates and a quantity of the liquid is maintained therein which liquid, due to centrifugal force, forms an annular ring of liquid in the shell. The pressure at the inlet of the Pitot tube is represented by centrifugal head plus velocity head. The oil enters the passage and is caused to flow through the outlet pipe. In the normal operation of the hydraulic system herein disclosed, there is no actual iiow of liquid needed but a pressure must be maintained. When there is no iiow through the Pitot tube channel, the oil in the shell merely ows past the Pitot tube and its head and as will be observed by reference to Fig. 5, the Pitot tube and its head are streamlined to minimize friction and resistance. The Pitot head is perfectly streamlined on its radius as illustrated. When the parts come to rest, some of the oil in the shell will be dumped but the oil will be maintained in the lower portion of the shell up to the level of the opening 39. Upon the commencement of operation, this volume of oil is suflicient to start the pump and supply the initial quantity of oil. To this end, it will be noted that the head of the Pitot tube is disposed near the periphery of the shell so that it will be at all times submerged.

Suitable means may be provided to keep the shell full of oil during operation. One such means may take the form of a lift pump of the Archimedes spiral type. The structure may comprise two sheet metal plates 50 and 5| placed face to face and secured to the hub at 52. The plate 5| is formed with two spiral grooves 53 and 54 which provide channels 55. These are open at their outer ends as at 56 where the plate 5| is provided with an aperture 51 and their inner ends communicate with inlet apertures leading into the shell as at 58. During rotation of the shell the channels lift the liquid and discharge the same into the shell and thus keep it full. A structure for keeping the shell full of oil by the operation system is shown in Fig. l herein. The partition 35 is provided with a trough formation 60, the lower end of which discharges oil into a formed groove 6| in the hub. In normal operation the oil in the sump is splashed and some of it falls into the trough 60 from where it flows through 6| into the shell. These two means for keeping the shell filled with oil may be used individually or together. The two Archimedes spirals are provided to keep the plates in balance.

The control mechanism as shown in Fig. 9 includes a clutch control cylinder 65 mounted on trunnions in bracket 66 so that it may rock and in this cylinder (Fig. 12) is a piston 6 4 having a piston rod 61. This piston rod has a pin and slot connection 68 with a control arm 69. The clutch shaft 28 has yoke member 1|) keyed thereto while the arm 69, which is of bell crank form, has an arm 1| operably connected to the yoke 19. The yoke has two abutments 12 While a bolt 13 is screw threaded through the arm 1| and it has a nut 14 screw threaded on its opposite end. In this way the control arm 69 and the rock shaft -are coupled together but the coupling can be adjusted. To make an adjustment the bolt 13 is turned on its screw threads in 1| thus changing the relative position of the control arm and the clutch rock shaft. After the adjustment is made the nut 14 is adjusted to engage one of the abutments 12. It is easily understood that the head of the bolt and nut 14 engage the abutments 12 so that rocking of the arm 69 causes rocking of the clutch shaft. This adjustment is for clutch facing wear as will later appear.

The pump outlet 41 is connected by a conduit 11 to a solenoid valve generally illustrated at 18. A conduit 19 extends from the valve and enters the cylinder 65 at 80 and connects to a passage 8| lwhich connects into the cylinder on the rod side of the piston (Figs. 8 and l2) A conduit 82 extends froin the valve and enters the cylinder at 83 through passage 84 and into the cylinder on the side of the piston opposite the rod 61. By a suitable operation o'f the valve, the pressure liquid may be introduced into either side of the cylinder while connecting the other side back to the sump. There is, what may be termed, an energizing cylinder 86 which is smaller than the cylinder 65 and a conduit 81 leads from the pump outlet 41 to one end of cylinder 86 as shown in Fig. 13, The piston 88 in this cylinder is acted upon by a spring 89 and it has a piston rod 9|) with an adjustable connection 8| to an arm 92. Whenever the pump is in operation, the liquid under pressure is transmitted into cylinder 86 and the piston 88 is shifted to the left hand endV of the cylinder as Fig. 13 is viewed.

The cylinder 86 has to do with the control of the engine throttle, an arrangement noW to be described. The usual throttle treadle as shown at 95 connects to 4the carburetor lever 96, through a link 91 and arms 98 and 99 mounted for rocking movement in unison, and a link or rod |90. When the treadlle 95 is depressed, the throttle arm 96 is rocked toward open position or clockwise as Fig. 9 is viewed. Rotatable with the crank arms 98 Iand 99 is an anm |82 connected by a link |93 with an arm |84 mounted on the clutch shaft 28.

Means are provided for coupling the clutch shaft with the throttle control so that when the vehicle is .mo-ving and the clutch is disengaged the movements of the .clutch governs throttle movement. To this end a coiled spring type of clutch is employed as shown in Fig. 10. There is a sleeve |81 keyed to the control lever 69, as of |08, and this sleeve has a flange |09 which is cutaway to provide an abutment H8. There is another interiitting sleeve positioned over the sleeve |81 as illustrated at E8 and it has a flange cut away to .form an abutment |2 (Fig. 18). The sleeve H3 is connected to the arm 92 and indeed the arm 92 may constitute a part of a small housing I5. Surrounding the two interfitting sleeves is a coiled spring |6, the ends of which are iiared outwardly at ||1 and i I8 in such a manner as to engage the abutments lll) and 2.

Surrounding the spring ||6 is sleeve |20 with clearance relative to the spring so that the sleeve is freely rotatable relative to the spring. This sleeve |26 has a yielda'ble connection with the arm |94. This yieldable connection takes the form of a torsion spring |2|, one end which at |22 engages the sleeve and the other end of which at |23 connects-to the flange of a sleeve |24 mounted on the clutch shaft 28 and to which the arm |94 is connected. There is an additional coupling which may be termed a safety coupling between sleeve |91 and sleeve ||3 and `which takes the form of a pin |26 positioned in a part of the sleeve .the sump chamber. .are shown as rectangular which is an expedient vto the passage |55 by an axial port |51.

Iliff; and engagingl ina slot |21 inf-the sleeve |13.

Ilfieslot is considerablywider than the diameter of the pin as will be seenbyreference to Fig. 18,

the purposes of which w-ilipresently appear.

`.'lhere is a single operation required of the operation inthe control ofthe entire mechanism,

-by-means of which the action of the clutch and thehydraulic system, is governed. This operation may be associated and preferably is associated with the mechanism for shifting the gears in the transmission through the means of the member 8: To this end, as shown in Figs. 1 and 14, there is a movable element 8a which may be directly Vconnected with the member 8 for shifting the gearsor connected thereto through suitable linkv age (not shown). VThere is a handle or knob connected'tothe member 8a yieldably as by means of coiled spring |3|. Themember 8a has an in- .sulatedf electrical contact ferrule |732 for contact withA the spring |3| and the spring is grounded ,afs Shown. An electrical conductor |34 connects tot-he solenoid; another electrical conductor |35 extends from the solenoid to a battery or other source of power |36 which is grounded as at |31.

I huswhen thespring contacts the member |32,

the solenoid is energized; The member 8a, near its end and between the contact l 32and the point of connection with the spring ISI, is of flattened construction as shown at |38 (Fig. 17). Pressure applied'by the hand of the operator on the knob in theplane of thedrawing in Fig. 14 will not re- Vsuit-inithe making of an electrical Contact. rlijhus the section |38 supportsthe spring |3|. However,

pressureapplied atV righta-ngles into or in the 4plaine o-f the drawings asFig. 16 is viewed fleXes the` spring |31 so that anV electrical contact may .bcv established. Thus an operator may allow his hand to restl upon the knob without making an electrical contact.

line-'VI connects and it has vtwo ports in communication Withtwo-ports |42 and |43 connecting into The ports in the valve body formation of the ports in such a valve and it will be understood the valve may be a die casting so thatthe ports may be readily formedV in such shape. The valve housing also has two passages .which lead to the lines 19 and'82.

Within thehousing is-a valve member |45 acted upon by a spring |45. The valve member has a port i5@ and a port 55E defined by lands |52, |53 and. 554. Thevalve also has a passage |515 passing therethrough from end to end and it has a Vcircuneerential groove which is connected The valve is in a position as shown in Fig. 1.4 which is a normal operating condition. The pressure `iuid from the pump enters at 11a, passes through Yport i 5i? into line i5 and into the engagement side of the control cylinder which is at the lefthand side as shown in Fig. 12, and thus the pisrton rod l is retracted. At this time the pressure liquidin the opposite side of the control piston .can `escape intothe sump through line 82, port .|5I and port |43. If there is any leakage past Vtheland l 52, the liquid enters the groove |55 and Vescapes through the port |42 into the sump. In

vaiveitsel isihydrauiically balanced andany oil or liquid which maybe trapped in the ends of the valve may flow through the axial passage |55 through radial Yport |51 into groove |56 and to the sump. When the solenoid is energized, the valve |45 is lifted magnetically to the position shown in Fig. 1,5. Inthis -position,itheV pressure liquid entering atY 'Ha passes through port |5|, which is closed from the exhaust |43 and through line 82 to the opposite end of the control cylinder. The liquid; in line TI may beI discharged through port |55 and port |42 back to the. sump. It isunderstoodrof course, that the system remains 1111 of liquid and the lines '19 and 82, remain full of liquid and the only liquidy discharged into thesump is that displaced by the movements of the control piston. It will berappreciated how shifting of the solenoid causes a shift ofthe controlpiston from one end of its cylinder to the other.

VIn order to provide. an easily accessible and outside clutch adjustment, there is a rod |55 which connects to apartof. the control arm69 at ,ii and this rod extends through a suitable abutment |52 where it is provided with a pair of suitable stop nuts |53, A spring |64 reacts against the stopI |162 and a n ut |55 screw threaded 011 the rod- Between the nut |55 and springrllfl is a washer |55 which is no nrotatably mounted on the rod Igand the nut and washer having an interengagernent atig'l comprising a recess in one and a teat on the other so that the nut maybe turned for, adjustment with a snap action with respect tothe washer for purposes which will.V presently appear.

In describing thel operation of the structure, various additional functions of some of the parts Willappearand itigbelieved to be most expedient to bring out these functions in a consideration of the operation so thatthe function will be better understood, andI appreciated. In a normal at rest condition of the vehicle with the engine idling, say at 500 orOOvR. P.- M. the clutch is open as showniinFig. 1. A tl this time, the driven shaft and the pump are notl operating. The springs 2U hold the,V clutch pressure plate retracted. Also thespring |64 pushes on rod |65 and ac tsthroughithe control arm 59, rock shaft 23 and through sleeve 3l! to swing the clutch levers toward the left as Fig. 1 is viewed. Thus the springs 2D Yand the outside spring |54 serve to hold the clutch disengaged under these circumstances. The adjustable nuts |53 provide a readily accessible outside adjustment for determining the amount'of-pressure plate retraction, and the clearancein disengagement. Upon acceleration the centrifugal. clutch begins to close as centrifugal force overcomes the action of the springs 2U andthe spring |64. The point of engagement can be varied byadjusting the tension on the springV |54 throughthe means of the nut |65. This provides a readily accessible outside adjustment for this purpose. Initially the connection-,between the yOke 72 and the arm 'H (Fig. V9) is set up for new clutch facings and the adjustment at this point may be made from time totime to accommodate for facingA wear. Upon acceleration, the centrifugal clutch will engage at a suitable R. P. M. above Aengine idling Speed. The centrifugal weightsasabove mentioned are relatively light so-that there is `a smooth initial engagement and assoonasthe driven shaft begins to rotate the pump beginsfto-function.

The pressure liquidV is transmitted through the v ilrewliichtbessositipnas Shawn. in .Eia le through the line 19 to the engagement side of the control piston which is the lefthand side as shown in Fig. 12. Movement of the piston rocks the clutch control shaft clockwise as Fig. 9 is viewed (counterclockwise as Fig. 1 is viewed) and exerts a pull on the clutch levers 24, thus tending to turn the clutch levers in a direction which aids and supplements centrifugal force. The centrifugal weights themselves may, for example, be arranged so as not to exert enough pressure to handle full engine torque until the engine is at about 2400 R. P. M., whereas the supplemental hydraulic force may be arranged to provide such supplemental pressure that full engine torque can be handled by the clutch at about 1200 R. P. M. These figures are only exemplary.

Upon deceleration of the vehicle, the centrifugal clutch in itself would disengage at a speed above engine idling speed or, for example, at about 700 or 800 R. P. M. But since the hydraulic system is functioning, the hydraulic pressure holds the clutch closed to a lower engine R. P. M. say, for example, about 300 R. P. M. Thus, the vehicle can .be slowed down and operated at a very low rate of speed. At this point the importance of the lost play between the clutch control piston and the clutch mechanism at 68 may be brought out. Forces applied to the clutch levers through the sleeve 30 places an end thrust on the engine crank shaft. When the control cylinder has been shifted to the end of its clutch engagement stroke, which is the right hand end of the cylinder as shown in Fig. 12, it is stopped by the abutment as shown. At speeds, say, for example, above 2400 R. P. M., centrifugal force increases but no further movement occurs in the hydraulic system. This additional centrifugal force causes a further collapse of the spring structure I4 in the driven disc and a flexing of the cover plate with the result that the `control arm 69 shifts in the slot 68 and the load exerted on the arm 69 by the piston is thereby relieved.

Let it be assumed that the vehicle was started from a standing position with the transmission gears in the box 6 set for a low gear ratio and that it is now desirable to shift in the higher gear ratio which requires clutch disengagement. The operator grasps the knob |30 and applies pressure for shifting the gears. The arrangement is such that pressure is applied in a direction so that the knob |30 is moved to the position shown in Fig. 16 and the electrical contact established between spring |3| and contact |32. This energizes the solenoid |40. The valve is lifted as shown in Fig. 15. The pressure liquid is now transmitted through port and line 82 to the clutch release side of the clutch control piston which is the right hand side as Fig. 12 is Viewed. This pushes the piston and projects its piston rod and swings the clutch control shaft 28 clockwise, as Fig. 1 is viewed, which, through the clutch control sleeve, the groove 34 and the involute teeth 25, swings the clutch levers to a disengaged position as shown in Fig. l. There will always be enough hydraulic pressure to perform this function, since .both the pressure and the centrifugal force increase with the square of the speed and are cooperate for this purpose. As the control piston is thus shifted, the liquid on the clutch engaging side of the piston is displaced through line 19, port |'50 and back into the sump chamber 36 through the port |42. After the gear shift has been made, the operator releases the knob |30 and the electrical contact is broken, the solenoid de-energized and the valve restored to the position shown in Fig. 14, whereupon the pressure liquid is transmitted through line 11, port 11a, port |50 and line 19 to the engagement side of the piston and the liquid on the opposing side of the piston is displaced through line 82, port |5| and back to the sump through port |43. This description of clutch engagement and disengagement has been given without regard to an additional automatic control of the engine throttle in order to first clarify the action of the clutch control cylinder and the flow of the pressure liquid.

There is, however, an automatic engine control which takes over the control of the throttle when the clutch is, for example, about one-third disengaged. This automatic control takes the throttle mechanism out of the control of the driver, substantially closes the throttle, so that the engine may decelerate toward idling speed and then after the gear shift has been made and the clutch is about two-thirds engaged, the -control of the throttle mechanism is restored to the driver. This is the purpose of the mechanism, largely shown in Fig. 10, and the reaction cylinder 86 as shown in Fig. 13.

It will .be observed that the reaction cylinder 86 is directly connected to the pressure outlet 41 so that in all normal operating conditions of the pump, the piston 88 is shifted against the spring 89 and positioned in the left hand end of its cylinder. The position of the piston 88 controls the position of the sleeve I |'3 to which it is connected through the arm 92 and therefore controls the position of the shoulder |I2 (Fig. 18). When the control piston starts to push the control arm 60 toward clutch disengagement position, the sleeve |01 is also rotated through its connection |08 with the arm 69. The direction of rotation of sleeve |01 is such that its abutment lit moves in the direction of the arrow illustrated in Fig. 18, which is upwardly on the sheet of drawings. The shoulder II'0, therefore, abuts the end I I1 of the spring clutch member l I6 and starts to rotate it. But the opposite end of the spring I I8 abuts the shoulder ||2 held positioned hydraulically by the piston 88. Only a few ounces of pressure is necessary to .be applied on the abutment ||`2 as this resistance is adequate for causing an expansion of the spring to establish a clutching engagement with the sleeve |20. As mentioned above this may occur when the clutch is about one-third disengaged. In the remaining two-thirds of the disengaging movement, the sleeve |20 is moved with the moving clutch mechanism, or in other words the shaft 28, and this moves the arm |04, to which the sleeve |20 is' connected through the,yieldable spring |2I. clockwise as Fig. 9 is viewed. As above pointed out the arm is connected through linkage shown to the throttle control lever 96. Therefore, in the remaining two-thirds of the disengaging movement of the clutch, the throttle is moved firmly but strongly back toward closed position, which is engine idling position, and the control treadle pedal is likewise pushed back to engine idling position against the weight of the foot of the operator. The energizing piston 88 functions to locate the abutment I2 in an energizing posin tion only when there is a supply of liquid under pressure. Therefore, it is only when the driven shaft 5 is operating Vthat the coil spring clutch becomes engaged. When the vehicle is standing at rest or when it decelerates to a substantially This movement of the arm |04 is counter-V at rest condition ,them throttle free `and Vcompletely. underthe coni/.relief the.Operator.

ItA will be appreciated that the clutchv..Control mechanism will move to complete disengaging position. Under some circumstanCS.,.thethrottle may be only partially open when the clutch is disengagedvand thereforedoes not have the range of movement that theclutch mechanism has. This is the reason for the use of the spring I 2 I. When the throttle has moved to closed position and can move no further, the clutch mechanism continues to move to full clutch disengagement positionV and the spring |2| yields to permit of this action. In the above,action, the rotationoi the spring VI I6 forces rotary movement of the sleeve I|3 and therefore forces the piston 88 to shiit to the rightasFig.V 13 is viewed against the pressure of the liquid. But this energizingcylinder is small and the liquid-is merely displaced back through the line 8l which connects to the outlet 41 and outlet line l1. The hydraulic pressure on the energizing piston-88 keeps the vvclutch springenergized through this entire period. Upon clutch engagement, the parts'move reversely and when the piston 88 reaches the endof its movement the abutment IIZ stops while the abutment III) follows the clutch engaging Aaction andthe expanding and energizing on thespringis discontinued. Thus the accelerator is rmly moved back from engine idling position to substantially the original position where it was coupled. with the clutch operating mechanismjand then it is released by the de-energization of the clutchspring II and restored to the control oi thedriver. Ii for any reason, the pistonmightgbe a little sluggish or lag behind the clutch mechanism in .clutch engaging movement, theauxiliary pin V|26 will pick up the sleeve I|3 and causev the sleeveand piston to return to normalenergizing position. This is merely ,a safety. factonm-The adjustment at 9| between the piston 88 and thearm a92 established the normal .position of the abutment I I2... Therefore, this determines thepoint inthe clutch engagement land disengagement .actionslwhere the throttle mechanism. is, .co,upled1to land released from,the clutch operatinglmechanism. As mentioned above theengagement may take Yplace when the. clutch is ,abollil., One-,third disengaged and may be discontinuedwhen the'clut'ch is about two-thirds engaged. l,

Accordingly, the driveiyof. the :vehicle i's required only to apply pressuredon,thegeaiyshift knob |39; this, starts the clutch disengagin'g ,action; the functioningL of` the throttleiishtaken away, from. the driver duringjclutch,disengagement and the throttle gradually vand firmly rnovedto closed position; when the operatorreleases' Ithe knob, after the gearshiituhas been matig the clutch starts4 its engagement-,Litho y, throttle control mechanism is irmly moved back toward open 60' position and then the v'zfontrol thereof isurestored to the driver at substantially the position itnwas taken away from the driver when the'v clutch1 is about two-thirds engage control of the engine'a'nd clutch engag ment and disengagement, in nthe normal operation of a vehicle. Yet it gives to ,the individual driver a wide latitude in which h is prerogatives as iehow he may ei'et i0 operate the venieie. In other words, it isat thend'ri'vrs lection at what speeds of vehicle rno've mentl gear is to be made. The driver niaypiiatetne vehicle indefinitely in any g'earhrgiarvdlessp silleed.n "Ihe engine may be controlled and operated" or raced while the vehicle is standing at'restbecause in the actuation of the throttle, the sleeve |20 freelyY oscillates relative to the coil spring I I 6. In other words, it is only inthe c ourse of a clutch dis'- engagement while the vehicle is moving that the spring I I6 is energized to cause the clutch mechanism to take over the control of the throttle. A modif-led form of control is shown in Figs. 19 and 20. In this form of control, the clutch and the hydraulic system is the same as that heretofore described and the modification relates to the control of the throttle. Such parts as have been heretofore described and which are the same in the modified form, bear the same reference characters and 1re-description is unnecessary. In this form the accelerator treadle is shown at |80, connected by a link ISI to a crank having an arm |82 and a yoke shaped arm1|83'. Carried in the yoke on trunnions I is acylinder acted upon by a. retractor springA |86. Within the cylinder is a piston |81 acted upon by a spring |88 and the piston is connected by a rod |89 tothe throttle lever |98. There is no mechanical connection between this throttle control and the clutch mechanism but a pressure line 81a connects into the cylinder at ISI and this pressure line connects at |92 to the pressure line 82 which is the disengagement pressure line for the control cylinder 65.

In normal operation with the clutch engaged,

the liquid pressure from the pump is. applied to:l

the control cylinder through the line I9 and therefore there is no pressure in the line82 or line 81a or in the cylinder |85. shifts the piston I8? t'o" a`normal"position at the right hand end of the cylinder as Fig.' 19 is viewed.' This spring |83' has suici'n't strength" so thatv when the accelerator is depressed the throttle is moved toward'open position by`i`orce transmitted' f through cylinder |85 and spring I88to the rodA |89.

However, when the clutch begins disengagement, by reason of the introduc'tinoi` liquid under pressure into line 82, the' pressure' liquid enters the cylinder I 8S andA pushes the" piston |87 to the opposite endof the`cylind`er`.' This shortens the coupling in the control line so that, even if the accelerator pedal y|88 is pushed all the way down, thestroke of the piston is long enough to cause a. movement of thenthrottle lever I'SI to substantially closed position.4 When the accelerator |88' is released and retracted bythe springnISB, the movement of the piston I8?" hydraulicallywwill cause the spring' |95 tombe compressed. vThus, although the operator Yrn'ayshiit the accelerator pedal ISD as he desires", the throttle control is disabled during Aclutch ,`dsel'lgigenflentj `Upon clutch engagement', however, the pressure liquid in the cylinder |35 is relieved and the piston returns to its normal extended lp'o'sitio'nlasi shown in Fig. 1.9 so that throttle controlV is reestablished`.

Iclaimr l. In an automotive vehiorlaean enginaan automatic clutch arranged to engage and disengage at about engineidling s'pfeled, driven means including a speedrchang'e transmission for transmitting engine torque, anropeiatlorcontrolled throttle ici' the engine, power means operatedby thevdriven meanseand under. the control o operatorror disengagingthe clutch and forc'ausing clutch eneaeerlrtlitt04 facilitate gear @harige in the, transmission, coupling means'as'sociateld with the power means andl 'I'.hifottle, said coiplihgA means being normally disengaged, ,operable byy the driven mgarlso coiliiitgmee I@ c'oiirlig means for engagement iipn nim/'effi nt Yof iii-e power Therefore the spring 88 means, so that when the driven means is operating the throttle is controlled by the power means in its actuation of the clutch and whereby, when the driven means decelerates to substantially at rest condition the throttle is freed from the power means and restored to the control of the operator.

2. In an automotive vehicle, an engine, an automatic clutch arranged to engage and disengage at about engine idling speed, driven means including a speed change transmission for transmitting engine torque, an operator controlled throttle for the engine, hydraulic clutch control means operated by the driven means and under the control of an operator for disengaging the clutch and for causing r'e-engagement of the clutch to facilitate gear change in the transmission, coupling means for connecting the clutch control means and throttle, said coupling means being normally disengaged, hydraulic means operable by the driven means for conditioning the coupling means for engagement upon movement of the hydraulic clutch control means, so that when the driven means is operating movements of the clutch control means governs the throttle and so that when the driven means decelerates to substantially at rest condition the throttle is freed from the clutch control means and its control restored to the operator.

3. In an automotive vehicle, an engine, an automatic clutch arranged to engage and disengage at about engine idling speed, driven means including a speed change transmission for transmitting engine torque, an operator controlled throttle for the engine, power clutch control means operated by the driven means and under the control of an operator for disengaging the clutch and for causing clutch engagement to facilitate gear change in the transmission, coupling means associated with the power clutch control means and throttle, said coupling means being normally disengaged for control of the throttle by the operator, means operable by the driven member for conditioning the coupling means so that the same remains disengaged for throttle movements under the control oi the operator when the driven means is operating, and so that the coupling means become engaged upon movement of the power clutch control means whereby, the throttle is controlled by movements of the clutch control means only when the driven member is operating.

4. In combination, an engine, an operator controlled throttle therefor, a gear change transmission for transmitting the engine torque, a clutch between the engine and the transmission arranged to be engaged and dis-engaged, power means for causing clutch disengagement, holding the clutch disengaged, and for causing clutch reengagement, means actuated by and during the clutch disengaging action for coupling the throttle to the power means and actuated by and during the action of clutch engagement for uncoupling the throttle and the power means, whereby the throttle is controlled by the power means from the time the clutch is partially disengaged, during clutch disengagement and until the clutch is partially re-engaged.

5. In combination, an engine, an operator controlled throttle therefor, a gear transmissionv for transmitting the engine torque, a clutch between the engine and the transmission arranged to be engaged and disengaged, power means under the control of the operator for causing clutch disengagement, holding the clutch disengaged, and for causing clutch re-engagement, means actuated by and during the clutch disengaging action for coupling the throttle to the power means and actuated by and during the action of clutch engagement for uncoupling the throttle and the power means, whereby the throttle is controlled by the power means from the time the clutch is partially disengaged, during clutch disengagement and until the clutch is partially reengaged.

6. In combination, an engine, an operator controlled throttle therefor, a gear change transmission for transmitting the torque, a clutch between the engine and the transmission arranged to be engaged and disengaged, a movable clutch control element which shifts in the clutch engaging and disengaging actions, means for disengaging the clutch and for causing clutch re-engagement, during which disengagement a gear change may be made, means for coupling the throttle to the clutch control element as it moves during the clutch disengaging action and before the clutch is disengaged, and for uncoupling the throttle and said element during the clutch engagement movement of the element after the clutch is partially engaged, whereby the throttle is automatically controlled by clutch movements at the times above mentioned and during the time the clutch is disengaged and restored to the operator after the clutch is partially engaged.

7. In combination, an engine, an operator controlled throttle therefor, a gear change transmission for transmitting the torque, a clutch between the engine and the transmission arranged to be engaged and disengaged, a movable clutch control element which shifts in the clutch engaging and disengaging actions, power means for disengaging the clutch, holding the clutch disengaged and causing clutch re-engagement, means operable at will by the operator for controlling the power means, and means for coupling the throttle to the clutch control element before the clutch is fully disengaged, and for releasing the coupling after the clutch is partially engaged, whereby the throttle is automatically controlled by clutch movements from a time beginning with partial clutch disengagement to a time When the clutch is partially re-engaged.

8. In combination, an engine, a throttle therefor, operator controlled means for actuating the throttle, a gear change transmission for transmitting engine torque, a clutch having driving and driven members between the engine and the transmission arranged to be engaged and disengaged for facilitating change of gears in the transmission, means for causing clutch disengagement and re-engagernent, said last named means and the throttle actuating means having related clutching elements including a coil spring, said elements being normally disengaged and means operable by the driven member of the clutch for causing the coil spring to be energized into clutching engagement with the related clutching element upon the disengaging action of the clutch and for causing the coil spring to be de-energized from clutching engagement upon re-engaging action of the clutch.

9. In combination, an engine, a throttle therefor, operator controlled means for actuating the throttle, a gear change transmission for transmitting engine torque, a clutch having driving and driven members between the engine and the transmission arranged to be engaged and disengaged for facilitating change of gears in the transmission, control means for causing clutch disengagement and 1re-engagement, hydraulic means for actuating the control means, said conm ,trol means and the throttle actuating means hav- 

